Research On Control System Of Forest Fire Fighting Canon And Extinguishing Shell

A pneumatic fire fighting cannon is a very effective tool in fighting against large-scale forest fires. Equipping fighting cannon with an advanced fire control system has a very important significance in fulfilling the cannon's performance. Meanwhile, the tree crown fire is a fatal major factor in the spread of forest fires. To control tree crown fire is an important way to extinguish forest fire. Thus, the fire extinguishing shell should be exploded at the height above the crown fire in order to extinguish crown fire. Therefore, this paper mainly studied the fire control system of pneumatic fire fighting cannon and electronic time fuze system of extinguishing shell which is against the tree crown fire.This subject derives from the project subsidized by the public special fund of the National Ministry of Science and Technology - "Remote forest fire fighting cannon, vehicle, and shell system"(PN: 2005DIB3J13) and the project subsidized by the State Forestry Adminstration - "The integrated system development of the remote, fast and secure forest fire fighting equipment"(PN: 2006-48). According to the characteristics and requirements of fire control system, this paper introduced the construction and the function of every part of the fire control system, the cannon control system design based on motion control card, which considers fire control computer as the core, was completed. At the same time, the electronic time fuze for the shells which considers MCU as the key was designed according to the working principal of the extinguishing shell. The fuze has advantages of small size and low working voltage. The precise timing can be accomplished and the fire temperature can be collected as well, when the temper, above crown fire, reaches threshold value, the shell exploded to fight against crown fire.After the shell is projected, the fuze timer begins to count. When the required timing is up, the parachute of the shell opens to decelerate, so that the external trajectory is quite special. Therefore, a mathematical model of external trajectory of the shell was established and the correction method was provided at the same time. On this basis the external trajectory database was constructed.The paper, finally, develops the fire control system platform. According to the target position that the operater inputs, the platform which can be simply and conveniently operated, can calculate shooting parameters and the time the shell installs, drives the cannon to move to destination location to project the shell.